“Pros and Cons section pretty much explains everything. i advice you to read my updated ruk30 review first to get an idea about this earphone: http://www.head-fi.org/products/koss-ruk-30k-noise-isolating-in-ear-stereophone-black/reviews/11943
there is not much to talk specifically about kdx200 here. it shares nearly the same driver with ruk30 and costs 3 times more while offers...” --vaziyetu

The KE/29 is lightweight with an in-the-ear design for deep bass and listening to music on the go. The KE/29 features a dynamic element that is positioned just outside the ear for extended frequency response of 15-20,000Hz. The KE/29 includes small, medium and large silicone ear cushions for a customized fit to enhance isolation when you want to eliminate ambient sounds that interfere with the...

The Koss KE29BZ is a portable isolation earbud stereophone. With a dynamic element for extended frequency response of 15-20,000 Hz. This compact design provides a robust sound. The KE29BZ is a lightweight, in-the-ear earbud for music on-the-go. The straight, dual entry 4 foot cord includes an inline volume control. A convenient carrying case provides protective storage and the small, medium...

The KE/29 is lightweight with an in-the-ear design for deep bass and listening to music on the go. The KE/29 features a dynamic element that is positioned just outside the ear for extended frequency response of 15-20,000Hz. The KE/29 includes small, medium and large silicone ear cushions for a customized fit to enhance isolation when you want to eliminate ambient sounds that interfere with the...

The KE/29 is lightweight with an in-the-ear design for deep bass and listening to music on the go. The KE/29 features a dynamic element that is positioned just outside the ear for extended frequency response of 15-20,000Hz. The KE/29 includes small, medium and large silicone ear cushions for a customized fit to enhance isolation when you want to eliminate ambient sounds that interfere with the...